1. an object's ID cannot change. However, the value of a reference can change to point to another object's ID.
2. Even if you schedule it, the schedule will still cling to the older object's ID.
%client.player.schedule(... will convert within the engine, to: objectID.schedule, which means the schedule is bound to that object, rather than the .player value.
If you want this to happen to .player after a certain time even if it changes, you'd do something like this:
%client.schedule(1000,setNormalScale);
And as a separate function:
function GameConnection::setNormalScale(%this)
{
if(isObject(%this.player))
%this.player.setScale("1 1 1");
}